Force installation in my/other language

Hello,
I have a problem with this issue. After investigation I realized that gimp will create a file in c:\Users\USER_NAME\.gimp-2.8\gimprc and put some kind of line with language. Gimp detecting method doesn't work correctly so I need to check reg key and upload for user (all users ) this file.
But it will be simple to be available some switch (I have know that is switch \CONFIGOVERRIDE - but for me uselessness).
There is better way to do this? Any advise, tips?

but I want without bat file - universal - without any additional files
Which environment variable exactly ?
set lang=fr for example?
Can I set this variable globally ? For me it doesn't work..
For now I can read from reg HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Nls\Language\Default
override gimprc (base gimprc is in C:\program files\GIMP 2\etc\bin\2.0 ? ) and make active setup...